The present invention relates to the field of brewing.
More particularly, the present invention relates to a method and apparatus for the quantitative analysis of alcohol and carbon dioxide in beer.
Currently, to test beer for alcohol (i.e. ethanol) content or any other component than CO.sub.2, it must first be de-gassed (i.e. the CO.sub.2 must be removed). This is because conventional laboratory techniques including gas chromatographic analyses are based on the exact measurement of a defined sample quantity (volume or weight); partially de-gassed or carbonated beer samples cannot be measured accurately because of the inherent instability of the sample specimen and as a consequence inaccurate analytical results are obtained. The upshot of the foregoing is, it is currently impossible to determine alcohol content in beer accurately with an in-line process gas chromatographic analyzer (GCA). Hence, de-gassification of discrete samples is done prior to alcoholic content determination by a GCA.
Unfortunately, however, when beer is de-gassified prior to analysis, it is inevitable that some ethanol is lost. This further complicates the problem of alcohol determination as the discrete sample which has been de-gassed will no longer be representative of the batch from which it originated.
A further problem associated with the use of a process GCA for ethanol determination is that solids (mainly carbohydrates and proteins) from the beer tend to accumulate in the GCA, necessitating its frequent dis-assembly for cleaning.
The object of the present invention is to provide an apparatus by which the alcohol concentration in a pressurized beer sample may be gauged without de-gassing the beer. A further object of the present invention is the design of an apparatus for use in the in-line chromatographic analysis of alcohol in beer which provides the required CIP (cleaning-in-place) for continuous operation.